The present invention relates to a High Security Lock, and more particularly to a magnetically actuated lock having no penetration of the key into the lock.
Such high security locks are currently in demand in the coin-operated machine industry, althrough this is by no means the limit of their usefulness. However, the coin-op industry is faced with special problems from the intensity of pilferage. In an effort to render the locks used more pick-proof, sophisticated pin-tumbler locks have been developed having axial tumblers disposed in a ring shape, limited access apertures and other features intended to impede picking. None of these efforts have succeeded in eliminating the key-hole, the focal point of picking attempts. While forcing of the coin enclosures is also a problem, it has been estimated that 90% of the theft losses in the coin-op laundromat field are from lock picking and keying, rather than forcing. A pick-proof lock would thus be a considerable advance in theft prevention.
A number of previous efforts in the direction of magnetically actuated locks have resulted in cumbersome and expensive devices which produced little in the way of added security and sophistication, and were poorly adapted to inexpensive production in volume. Such locks often offered little advantage over a well made pin tumbler lock so far as picking and forcing were concerned. One group of prior art magnetic locks are those wherein a small number of locks are intended to be operated by a large number of card-sized magnetized keys. Such locks require a slot for penetration of the card into the lock body, thus laying the lock open to various attacks through the slot.
Prior locks also offered little or no security against the problem present by a stolen key as no action was required by the operator beyond insertion of the correct key into the lock. Most such locks also had no penalty apparatus to discourage tampering, so that they could ultimately be defeated by a person having adequate time to apply to the tampering effort. In most such locks, the correct location for application of the key to the lock is obvious, as there is a keyhole or slot.